At 02.08 hours on 19 August 1941, U-559 fired a salvo of four torpedoes at convoy OG-71 about 600 miles west of Ushant, observed one hit and heard one double and one single detonation. The assessment of the BdU was that two ships of 17,000 grt had been sunk and another ship of 7000 grt damaged. In fact, only the Alva (Master Cyril Spenser Palmer) was sunk in this attack. One crew member was lost.

The master, ten crew members and two gunners were picked up by the Clonlara, but nine of them died when this vessel was sunk by U-564 (Suhren) on 22 August. The survivors were picked up by HMS Campion (K 108) (LtCdr A. Johnson, RNVR) and landed at Gibraltar on 24 August. Eight crew members and three gunners were picked up by the Empire Oak which was sunk by the same U-boat later on 22 August. Four shipwrecked men from Alva were lost and the survivors picked up by HMS Campanula (K 18) (LtCdr R.V.E. Case, DSC, RD, RNR), transferred to HMS Velox (D 34) (LtCdr E.G. Roper, DSC, RN) and landed at Gibraltar on 25 August.